Rock Identifier

Category

Sedimentary Or Igneous (Secondary Formation)

Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.

Learn about Sedimentary Or Igneous (Secondary Formation) in the encyclopedia

Banded Iron Formation

Banded Iron Formation

Itabirite

Jaspillite

Carbonatite

Conglomerate

Quartzite Sandstone

Quartzite Sandstone

Breccia

Ironstone

Lamproite

Troctolite

Basalt

Gabbro

Small weathered mineral/rock fragment (Uncertain from image; possibly quartz-rich sandstone or a feldspar-bearing rock) — mineral

Small weathered mineral/rock fragment

Uncertain from image; possibly quartz-rich sandstone or a feldspar-bearing rock

Quartz Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Banded Agate (Silicon Dioxide (SiO2) - Chalcedony) — sedimentary

Banded Agate

Silicon Dioxide (SiO2) - Chalcedony

Limonite with Trace Fossils (Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)) — sedimentary

Limonite with Trace Fossils

Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)

Agate (translucent water-worn pebble) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Agate (translucent water-worn pebble)

Cryptocrystalline Quartz (SiO2)

Agate (Agate (Silicon Dioxide, SiO2)) — mineral

Agate

Agate (Silicon Dioxide, SiO2)

Specular Hematite (Specularite) (Iron Oxide (Fe2O3)) — mineral

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Carnelian (SiO2 (Silicon Dioxide) - Translucent Chalcedony) — mineral

Carnelian

SiO2 (Silicon Dioxide) - Translucent Chalcedony

Mica schist (likely biotite–muscovite schist) (Mica schist; chiefly quartz and mica minerals (muscovite KAl₂(AlSi₃O₁₀)(OH)₂ and/or biotite)) — metamorphic

Mica schist (likely biotite–muscovite schist)

Mica schist; chiefly quartz and mica minerals (muscovite KAl₂(AlSi₃O₁₀)(OH)₂ and/or biotite)

Weathered granitoid (likely granite or granodiorite) (Granite–granodiorite; primarily quartz, feldspar, and mica) — igneous

Weathered granitoid (likely granite or granodiorite)

Granite–granodiorite; primarily quartz, feldspar, and mica

Golden Calcite (Calcium Carbonate (CaCO3)) — mineral

Golden Calcite

Calcium Carbonate (CaCO3)

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Honey Calcite (Calcium Carbonate (CaCO3)) — mineral

Honey Calcite

Calcium Carbonate (CaCO3)

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Quartz Geode (Silicon Dioxide (SiO2) - Crystalline Quartz) — mineral

Quartz Geode

Silicon Dioxide (SiO2) - Crystalline Quartz

Quartz (Small Pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz (Small Pebble)

Silicon Dioxide (SiO2)

Quartz Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Limonite / Ironstone Nodule (Hydrated Iron Oxide (FeO(OH)·nH2O)) — sedimentary

Limonite / Ironstone Nodule

Hydrated Iron Oxide (FeO(OH)·nH2O)

Sandstone Concretion with Quartz Center (Sedimentary Clastic Rock (SiO2 matrix with Quartz core)) — sedimentary

Sandstone Concretion with Quartz Center

Sedimentary Clastic Rock (SiO2 matrix with Quartz core)

Blue Chalcedony (Silicon Dioxide (SiO2)) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Mica-rich metamorphic rock, likely biotite schist (Biotite–quartz schist; probable composition of quartz, biotite, feldspar, and minor sulfide or iron-oxide minerals) — metamorphic

Mica-rich metamorphic rock, likely biotite schist

Biotite–quartz schist; probable composition of quartz, biotite, feldspar, and minor sulfide or iron-oxide minerals

Yellow Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Limonite (Goethite/Ironstone) (Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O) — mineral

Limonite (Goethite/Ironstone)

Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O

Quartz (Clear to Smokey) (Silicon Dioxide (SiO2)) — mineral

Quartz (Clear to Smokey)

Silicon Dioxide (SiO2)

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Chert (Iron-stained) (Chert (SiO2)) — sedimentary

Chert (Iron-stained)

Chert (SiO2)

Quartz (Jasper / Chert) (Silicon Dioxide (SiO2)) — sedimentary

Quartz (Jasper / Chert)

Silicon Dioxide (SiO2)

Milky quartz crystal cluster (Quartz (silicon dioxide, SiO₂)) — mineral

Milky quartz crystal cluster

Quartz (silicon dioxide, SiO₂)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

Citrine and Quartz (Silicon Dioxide (SiO2)) — mineral

Citrine and Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine/Yellow Jasper) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Yellow Jasper)

Silicon Dioxide (SiO2)

Calcite (Calcium Carbonate (CaCO3)) — mineral

Calcite

Calcium Carbonate (CaCO3)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Lepidolite (Lepidolite [K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2]) — Mineral

Lepidolite

Lepidolite [K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2]

Mica-rich rock, likely mica schist (Mica schist, composed chiefly of muscovite and/or biotite with quartz and feldspar) — metamorphic

Mica-rich rock, likely mica schist

Mica schist, composed chiefly of muscovite and/or biotite with quartz and feldspar

Weathered foliated metamorphic rock, likely schist or gneiss (Micaceous schist/gneiss; composition likely quartz, feldspar, mica, and altered mafic minerals) — metamorphic

Weathered foliated metamorphic rock, likely schist or gneiss

Micaceous schist/gneiss; composition likely quartz, feldspar, mica, and altered mafic minerals

Ferruginous Quartz (Silicon Dioxide with Hematite/Limonite inclusions (SiO2 + Fe2O3)) — mineral

Ferruginous Quartz

Silicon Dioxide with Hematite/Limonite inclusions (SiO2 + Fe2O3)

Small rounded pebble, likely quartz-rich sandstone or granitoid fragment (Uncertain; probable quartz/feldspar-bearing lithic pebble) — sedimentary

Small rounded pebble, likely quartz-rich sandstone or granitoid fragment

Uncertain; probable quartz/feldspar-bearing lithic pebble

Jasper or Chert with Quartz Vugs (Silicon Dioxide (SiO2)) — sedimentary

Jasper or Chert with Quartz Vugs

Silicon Dioxide (SiO2)

Ironstone Concretion / Goethite-Hematite Nodule (Goethite/Hematite (α-FeO(OH) / Fe2O3)) — sedimentary

Ironstone Concretion / Goethite-Hematite Nodule

Goethite/Hematite (α-FeO(OH) / Fe2O3)